/* =====================================================================
   Học viện Claude · Elite Capital — giao diện v2
   Bố cục: header navy + thanh danh mục, hero + thẻ số liệu,
   sidebar bộ lọc + lưới thẻ buổi học. Màu nhận diện Elite Capital.
   Muốn đổi màu nhấn: sửa --accent / --accent-hover bên dưới.
   ===================================================================== */
@import url('https://fonts.googleapis.com/css2?family=Montserrat:wght@600;700;800;900&family=Be+Vietnam+Pro:wght@400;500;600;700;800&family=JetBrains+Mono:wght@500;700&display=swap&subset=vietnamese');

:root{
  --navy:#3A3A3C;          /* nền header, nút chính */
  --navy-dark:#2B2B2D;
  --accent:#3089CA;        /* xanh Elite Capital — màu nhấn */
  --accent-hover:#226AA0;
  --accent-soft:#EAF3FB;
  --hot:#E8862A;           /* nhãn "ĐẦY ĐỦ" */
  --blue:#1E5A96;
  --green:#0E7C46;
  --teal:#3FA66A;
  --violet:#6D4A9E;
  --gold:#C9A227;
  --ink:#1B2333;
  --sub:#5A6683;
  --line:#E4E8F1;
  --bg:#F3F5FA;
  --card:#FFFFFF;
  --fh:'Montserrat',sans-serif;
  --fb:'Be Vietnam Pro','Segoe UI',system-ui,sans-serif;
  --fm:'JetBrains Mono',ui-monospace,Consolas,monospace;
}
*{margin:0;padding:0;box-sizing:border-box}
html{scroll-behavior:smooth}
body{font-family:var(--fb);color:var(--ink);background:var(--bg);-webkit-font-smoothing:antialiased;line-height:1.55}
a{text-decoration:none;color:inherit}
img{max-width:100%;display:block}
button{font:inherit}

/* ===== HEADER ===== */
header.top{position:sticky;top:0;z-index:60;background:linear-gradient(120deg,var(--navy),var(--navy-dark));color:#fff;border-bottom:3px solid var(--accent)}
.hbar{max-width:1340px;margin:0 auto;padding:12px 20px;display:flex;align-items:center;gap:16px;flex-wrap:wrap}
.brand{display:flex;align-items:center;gap:11px;font-family:var(--fh);font-weight:800;font-size:17px;white-space:nowrap;color:#fff}
.brand .mk{height:40px;padding:3px 9px;border-radius:9px;background:#fff;display:inline-flex;align-items:center;box-shadow:0 1px 4px rgba(0,0,0,.12)}
.brand .mk img{height:32px;width:auto}
.search{flex:1;min-width:230px;max-width:640px;position:relative}
.search input{width:100%;height:42px;border-radius:999px;border:none;padding:0 18px 0 44px;font-family:var(--fb);font-size:14.5px;background:#fff;color:var(--ink)}
.search input:focus{outline:2px solid var(--accent)}
.search .ic{position:absolute;left:16px;top:50%;transform:translateY(-50%);color:var(--sub);font-size:16px}
.star{font-family:var(--fm);font-size:12.5px;color:#BFE0F7;background:rgba(255,255,255,.08);border:1px solid rgba(255,255,255,.18);border-radius:999px;padding:7px 14px;white-space:nowrap}
.cats{background:var(--navy-dark);border-bottom:1px solid rgba(255,255,255,.08)}
.cats .in{max-width:1340px;margin:0 auto;padding:11px 20px;display:flex;gap:9px;flex-wrap:wrap}
.pill{font-size:13px;font-weight:600;color:#CDD8EE;background:rgba(255,255,255,.07);border:1px solid rgba(255,255,255,.16);border-radius:999px;padding:7px 15px;cursor:pointer;transition:.14s;display:inline-flex;align-items:center;gap:7px}
.pill:hover{background:rgba(255,255,255,.14);color:#fff}
.pill.active{background:var(--accent);border-color:var(--accent);color:#fff;font-weight:700}
.dt{width:9px;height:9px;border-radius:3px;display:inline-block;flex:0 0 auto}

/* ===== HERO ===== */
.hero{background:#fff;border-bottom:1px solid var(--line)}
.hero .in{max-width:1340px;margin:0 auto;padding:26px 20px 24px;display:grid;grid-template-columns:1.5fr 1fr;gap:28px;align-items:center}
.ey{font-family:var(--fm);font-size:11.5px;font-weight:700;letter-spacing:.14em;text-transform:uppercase;color:var(--accent)}
.hero h1{font-family:var(--fh);font-weight:900;font-size:30px;line-height:1.12;margin:8px 0 10px;color:var(--navy);letter-spacing:-.01em}
.hero h1 .o{color:var(--accent)}
.hero p{color:var(--sub);font-size:15px;max-width:58ch}
.hero p b{color:var(--ink)}
.stats{display:grid;grid-template-columns:1fr 1fr;gap:12px}
.stat{background:var(--bg);border:1px solid var(--line);border-radius:13px;padding:14px 16px}
.stat .big{font-family:var(--fh);font-weight:900;font-size:26px;color:var(--navy);line-height:1}
.stat .big .o{color:var(--accent)}
.stat .lb{font-size:12.5px;color:var(--sub);margin-top:4px}
.stat .lb .go{color:var(--accent);font-weight:700}
a.stat{display:block;transition:transform .15s,box-shadow .15s,border-color .15s}
a.stat:hover{transform:translateY(-2px);box-shadow:0 12px 26px rgba(22,38,92,.12);border-color:var(--accent)}

/* ===== APP: sidebar + content ===== */
.app{max-width:1340px;margin:0 auto;padding:22px 20px 40px;display:grid;grid-template-columns:252px 1fr;gap:24px;align-items:start}
.side{position:sticky;top:132px}
.panel{background:#fff;border:1px solid var(--line);border-radius:14px;margin-bottom:14px;overflow:hidden;box-shadow:0 4px 16px rgba(22,38,92,.04)}
.phead{display:flex;align-items:center;gap:9px;padding:14px 16px;cursor:pointer;user-select:none;width:100%;background:none;border:none;text-align:left}
.phead .d{color:var(--accent);font-size:14px}
.phead .t{flex:1;font-family:var(--fh);font-size:12.5px;font-weight:800;letter-spacing:.04em;text-transform:uppercase;color:var(--navy)}
.phead .chev{color:var(--sub);font-size:12px;transition:transform .18s}
.panel.collapsed .chev{transform:rotate(-90deg)}
.pbody{padding:0 12px 12px;max-height:600px;overflow:hidden;transition:max-height .22s,padding .22s}
.panel.collapsed .pbody{max-height:0;padding-top:0;padding-bottom:0}
.opt{display:flex;align-items:center;gap:10px;padding:9px 10px;border-radius:9px;cursor:pointer;font-size:14px;color:var(--ink);transition:background .12s;width:100%;background:none;border:none;text-align:left}
.opt:hover{background:#F3F5FB}
.opt.on{background:var(--accent);color:#fff;font-weight:600}
.opt.on .dt{background:#fff!important}
.opt .n{flex:1}
.opt .c{font-family:var(--fm);font-size:11.5px;color:var(--sub)}
.opt.on .c{color:#DCEEFB}
.tipbox{padding:4px 0 2px;font-size:12.5px;color:#78350F;line-height:1.5}
.tipbox .b{background:#FFFBEB;border:1px solid #FCD34D;border-radius:10px;padding:11px 12px}
.tipbox b{color:#7A3D06}
.navgrp+.navgrp{margin-top:2px}
.navhead{display:flex;align-items:center;gap:9px;padding:9px 10px;border-radius:9px;cursor:pointer;font-size:14px;transition:background .12s;width:100%;background:none;border:none;text-align:left}
.navhead:hover{background:#F3F5FB}
.navgrp.open>.navhead{background:#F6F8FD}
.navhead .n{flex:1;font-weight:600;color:var(--ink)}
.navhead .c{font-family:var(--fm);font-size:11px;color:var(--sub)}
.navhead .cv{color:var(--sub);font-size:10px;transition:transform .18s}
.navgrp.open .navhead .cv{transform:rotate(90deg)}
.navsub{max-height:0;overflow:hidden;transition:max-height .24s;margin-left:4px;border-left:2px solid var(--line);padding-left:4px}
.navgrp.open .navsub{max-height:520px}
.navitem{display:flex;gap:9px;align-items:baseline;padding:7px 9px;border-radius:7px;cursor:pointer;font-size:12.5px;color:var(--sub);transition:.12s}
.navitem:hover{background:#F2F8FD;color:var(--ink)}
.navitem .bn{font-family:var(--fm);font-size:10.5px;font-weight:700;color:var(--navy);flex:0 0 auto}
.navitem.full .bn{color:var(--accent)}
.navitem .tx{flex:1;line-height:1.35}

/* ===== TOOLBAR ===== */
.toolbar{display:flex;align-items:center;justify-content:space-between;margin-bottom:14px;flex-wrap:wrap;gap:10px}
.toolbar .n{font-size:15px;color:var(--sub)}
.toolbar .n b{color:var(--ink);font-weight:700}
.tright{display:flex;align-items:center;gap:8px}
.dd{position:relative}
.dd .bt{display:inline-flex;align-items:center;gap:8px;background:#fff;border:1px solid var(--line);border-radius:10px;padding:9px 14px;font-size:13.5px;font-weight:600;color:var(--ink);cursor:pointer}
.dd .bt:hover{border-color:var(--accent)}
.dd .menu{position:absolute;right:0;top:calc(100% + 6px);background:#fff;border:1px solid var(--line);border-radius:12px;box-shadow:0 18px 40px rgba(22,38,92,.16);padding:6px;min-width:220px;z-index:30;display:none}
.dd.open .menu{display:block}
.dd .menu button{display:block;width:100%;text-align:left;background:none;border:none;padding:9px 12px;border-radius:8px;font-size:14px;color:var(--ink);cursor:pointer}
.dd .menu button:hover{background:#F3F5FB}
.dd .menu button.on{color:var(--accent);font-weight:700}
.mobtoggle{display:none}

/* ===== TẦNG ===== */
.tangband{display:flex;align-items:center;gap:12px;margin:26px 0 6px}
.tangband:first-child{margin-top:2px}
.tangband .code{font-family:var(--fm);font-size:12.5px;font-weight:700;color:#fff;border-radius:7px;padding:5px 11px}
.tangband h2{font-family:var(--fh);font-size:19px;font-weight:800;color:var(--navy)}
.tangband .cnt{font-family:var(--fm);font-size:11.5px;color:var(--sub);margin-left:auto}
.tangdesc{font-size:13.5px;color:var(--sub);margin:0 0 14px 2px}

/* ===== CARDS ===== */
.grid{display:grid;grid-template-columns:repeat(auto-fill,minmax(300px,1fr));gap:18px}
.card{background:var(--card);border:1px solid var(--line);border-radius:16px;overflow:hidden;display:flex;flex-direction:column;box-shadow:0 4px 14px rgba(22,38,92,.05);transition:transform .16s,box-shadow .16s}
.card:hover{transform:translateY(-3px);box-shadow:0 16px 34px rgba(22,38,92,.13)}
.card.flash{animation:fl 1.3s ease 1}
@keyframes fl{0%,100%{box-shadow:0 4px 14px rgba(22,38,92,.05)}25%{box-shadow:0 0 0 3px var(--accent)}}
.cover{height:118px;position:relative;display:flex;align-items:flex-end;padding:14px 16px;color:#fff;overflow:hidden}
.cover::after{content:"";position:absolute;inset:0;background:radial-gradient(120% 100% at 85% 0,rgba(255,255,255,.18),transparent 55%)}
.cover .bk{position:absolute;right:14px;top:12px;font-size:28px;opacity:.9}
.cover .bn{position:relative;z-index:1;font-family:var(--fm);font-size:11.5px;font-weight:700;letter-spacing:.1em;background:rgba(0,0,0,.22);border:1px solid rgba(255,255,255,.25);border-radius:7px;padding:4px 10px}
.cover .hot{position:absolute;z-index:1;left:14px;top:12px;background:var(--hot);color:#fff;font-family:var(--fh);font-size:10px;font-weight:800;letter-spacing:.05em;padding:3px 9px;border-radius:6px}
.t1 .cover{background:linear-gradient(140deg,#3089CA,#3A3A3C 78%)}
.t2 .cover{background:linear-gradient(140deg,#3FA66A,#3A3A3C 78%)}
.card.plain .cover{filter:saturate(.55) brightness(.92)}
.cbody{padding:15px 16px 17px;display:flex;flex-direction:column;flex:1}
.cat{font-family:var(--fh);font-size:10.5px;font-weight:800;letter-spacing:.07em;text-transform:uppercase;color:var(--accent)}
.card.plain .cat{color:var(--sub)}
.ttl{font-family:var(--fh);font-weight:800;font-size:16px;color:var(--ink);line-height:1.26;margin:4px 0 3px}
.status{font-size:12px;color:var(--sub);margin-bottom:11px;display:flex;align-items:center;gap:6px}
.status .full{color:var(--green);font-weight:700}
.status .soon{color:#B4610F;font-weight:600}
.rows{border:1px solid var(--line);border-radius:11px;overflow:hidden;margin-bottom:13px}
.row{display:flex;align-items:center;gap:10px;padding:9px 12px;border-bottom:1px solid var(--line);font-size:13px}
.row:last-child{border-bottom:none}
a.row:hover{background:#F2F8FD}
.row .fi{flex:0 0 auto;width:25px;height:25px;border-radius:6px;display:grid;place-items:center;font-size:13px}
.row .fn{flex:1;font-weight:600;color:var(--ink)}
.row .arr{color:var(--accent);font-weight:800}
.row.off{opacity:.55}
.row.off .fn{color:var(--sub);font-weight:500}
.row .sn{font-family:var(--fm);font-size:9px;color:#9AA3B6;border:1px dashed #C7CEDD;border-radius:5px;padding:1px 6px}
.fi.slide{background:#EAF1FB;color:var(--blue)}
.fi.gt{background:#FFF2E6;color:var(--hot)}
.fi.tl{background:#E7F6EE;color:var(--green)}
.fi.tep{background:#EDEFF6;color:var(--navy)}
.fi.vp{background:#EDE7F6;color:var(--violet)}
.ctas{margin-top:auto;display:flex;gap:8px}
.cbtn{flex:1;display:inline-flex;align-items:center;justify-content:center;gap:7px;font-size:13px;font-weight:700;padding:10px;border-radius:10px;border:1px solid var(--line);color:var(--navy);background:#fff;transition:.14s}
a.cbtn:hover{border-color:var(--accent);color:var(--accent-hover)}
.cbtn.pri{background:var(--navy);color:#fff;border-color:var(--navy)}
a.cbtn.pri:hover{background:var(--accent);border-color:var(--accent);color:#fff}
.cbtn.off{color:#A8B0C2;cursor:default}
.empty{text-align:center;padding:60px 20px;color:var(--sub)}
.empty .big{font-size:40px;margin-bottom:10px}
.lockrow{display:flex;gap:14px;align-items:flex-start;background:#fff;border:1px dashed #C7CEDD;border-radius:14px;padding:18px 20px;margin-top:28px}
.lockrow .ic{font-size:22px}
.lockrow b{font-family:var(--fh);color:var(--navy);display:block;margin-bottom:2px}
.lockrow p{font-size:13.5px;color:var(--sub)}
.foot{border-top:1px solid var(--line);margin-top:34px;padding:24px 0 8px;text-align:center;color:var(--sub);font-size:12.5px}
.foot b{color:var(--navy)}

/* =====================================================================
   TRANG BÀI HỌC (giáo trình, tài liệu mẫu, văn phòng số)
   ===================================================================== */
.lesson-top{position:sticky;top:0;z-index:60;background:linear-gradient(120deg,var(--navy),var(--navy-dark));border-bottom:3px solid var(--accent)}
.lesson-top .wrap{max-width:1340px;margin:0 auto;padding:12px 20px;display:flex;align-items:center;gap:16px;flex-wrap:wrap}
.lesson-top nav{margin-left:auto;display:flex;gap:6px;flex-wrap:wrap}
.lesson-top nav a{color:#CDD8EE;font-weight:600;font-size:13.5px;padding:7px 14px;border-radius:999px;border:1px solid transparent}
.lesson-top nav a:hover{background:rgba(255,255,255,.1);color:#fff}
.lesson-top nav a.on{border-color:rgba(255,255,255,.25);color:#fff;background:rgba(255,255,255,.08)}
.lesson-top nav a.cta{background:var(--accent);color:#fff}
.lesson-head{background:#fff;border-bottom:1px solid var(--line)}
.lesson-head .in{max-width:900px;margin:0 auto;padding:26px 22px 24px}
.lesson{max-width:900px;margin:0 auto;padding:30px 22px 60px}
.breadcrumb{color:var(--sub);font-size:13px;font-weight:600;margin-bottom:12px;font-family:var(--fm)}
.breadcrumb a{color:var(--accent)}
.backbtn{display:inline-flex;align-items:center;gap:8px;background:#fff;border:1px solid var(--line);border-radius:999px;padding:8px 16px;font-weight:700;font-size:13.5px;color:var(--navy);margin-bottom:14px}
.backbtn:hover{border-color:var(--accent);color:var(--accent)}
.fab-back{position:fixed;left:20px;bottom:22px;z-index:70;display:inline-flex;align-items:center;gap:8px;background:var(--navy);color:#fff;border-radius:999px;padding:11px 18px;font-weight:700;font-size:14px;box-shadow:0 8px 24px rgba(17,29,48,.35)}
.fab-back:hover{background:var(--accent)}
.tag{display:inline-block;background:var(--accent-soft);color:var(--accent-hover);font-size:12px;font-weight:700;padding:5px 12px;border-radius:7px;margin-bottom:10px;font-family:var(--fm);letter-spacing:.04em}
.lesson-head h1,.lesson h1{font-family:var(--fh);font-size:clamp(24px,3.6vw,32px);color:var(--navy);font-weight:900;line-height:1.14;margin:0 0 8px}
.lesson-head .sub{color:var(--sub);font-size:16px}
.lesson h2{font-family:var(--fh);font-size:21px;color:var(--navy);font-weight:800;margin:38px 0 12px;padding-top:16px;border-top:1px solid var(--line)}
.lesson h3{font-family:var(--fh);font-size:16.5px;color:var(--accent-hover);font-weight:800;margin:24px 0 8px}
.lesson p,.lesson li{font-size:16px;color:var(--ink)}
.lesson p{margin:0 0 12px}
.lesson ul,.lesson ol{margin:8px 0 14px 22px}
.lesson li{margin:5px 0}
.lesson table{width:100%;border-collapse:separate;border-spacing:0;margin:16px 0;font-size:14.5px;background:#fff;border:1px solid var(--line);border-radius:12px;overflow:hidden}
.lesson th{background:#F6F8FD;color:var(--navy);text-align:left;padding:10px 12px;font-weight:700;font-family:var(--fh);font-size:13px}
.lesson td{border-top:1px solid var(--line);padding:10px 12px;vertical-align:top}
.lesson blockquote{margin:16px 0;padding:14px 18px;background:var(--accent-soft);border-left:4px solid var(--accent);border-radius:0 12px 12px 0;color:var(--ink)}
.lesson code{background:#EDEFF6;padding:2px 7px;border-radius:6px;font-size:13.5px;font-family:var(--fm)}
.lesson hr{border:none;border-top:1px solid var(--line);margin:30px 0}
.callout{background:var(--accent-soft);border:1px solid #CFE3F5;border-radius:12px;padding:14px 18px;margin:16px 0}
.callout.warn{background:#FFFBEB;border-color:#FCD34D;color:#5B3A0A}
.obox{background:#fff;border:1px solid var(--line);border-left:4px solid var(--hot);border-radius:0 12px 12px 0;padding:14px 18px;margin:12px 0;box-shadow:0 4px 14px rgba(22,38,92,.04)}
.obox b{color:var(--navy)}
.pill-row{display:flex;gap:10px;flex-wrap:wrap;margin:16px 0}
.btn{display:inline-flex;align-items:center;gap:8px;font-weight:700;font-size:14px;padding:11px 20px;border-radius:10px;border:1px solid transparent;cursor:pointer;transition:.14s}
.btn-primary{background:var(--navy);color:#fff}
.btn-primary:hover{background:var(--accent)}
.btn-ghost{background:#fff;border-color:var(--line);color:var(--navy)}
.btn-ghost:hover{border-color:var(--accent);color:var(--accent)}
.mina{background:linear-gradient(135deg,var(--navy),#2D4A63);color:#fff;border-radius:16px;padding:26px;display:grid;grid-template-columns:1.3fr 1fr;gap:24px;align-items:center;margin:18px 0}
.mina h3{font-size:20px;font-weight:800;color:#fff;margin:6px 0 8px}
.mina p{color:#CDD8EE;margin:0}
.mina .ey{color:#9CCBEE}
.mina .diagram{background:rgba(255,255,255,.07);border:1px solid rgba(255,255,255,.14);border-radius:14px;padding:14px;display:grid;grid-template-columns:repeat(5,1fr);gap:7px;text-align:center}
.mina .node{background:rgba(255,255,255,.08);border-radius:9px;padding:9px 4px;font-size:10.5px;font-weight:600;color:#EAEEF3}
.mina .node.hub{grid-column:1/-1;background:var(--accent);color:#fff;font-weight:800;font-size:12.5px;padding:11px}
.site-footer{border-top:1px solid var(--line);background:#fff;padding:22px 0}
.site-footer .wrap{max-width:900px;margin:0 auto;padding:0 22px;display:flex;gap:14px;align-items:center;justify-content:center;flex-wrap:wrap;text-align:center}
.site-footer img{height:34px}
.site-footer small{color:var(--sub);font-size:12.5px}

/* ===== RESPONSIVE ===== */
@media(max-width:900px){
  .hero .in{grid-template-columns:1fr;gap:18px}
  .app{grid-template-columns:1fr}
  .side{position:static}
  #sideWrap{display:none}
  #sideWrap.show{display:block}
  .mobtoggle{display:inline-flex;align-items:center;gap:7px;font-size:13px;font-weight:700;color:var(--navy);background:#fff;border:1px solid var(--line);border-radius:10px;padding:9px 13px;cursor:pointer}
  .mina{grid-template-columns:1fr}
  .lesson-top nav a:not(.cta){display:none}
}
@media(max-width:560px){
  .hbar{gap:10px}
  .star{display:none}
  .search{order:3;flex-basis:100%}
  .hero h1{font-size:24px}
  .grid{grid-template-columns:1fr}
  .side{top:auto}
  .fab-back{left:14px;bottom:14px;padding:10px 15px}
}

/* logo ngang Elite Capital trên nền than chì */
.hlogo{height:34px;width:auto}
.brand .sep{width:1px;height:28px;background:rgba(255,255,255,.22)}
@media(max-width:560px){.brand .sep,.brand .bt-name{display:none}}